The magazine well portion of that is pretty much exactly the same as what Im starting to design, even down to the exposed original foregrip. I like how the stock trigger guard is blended in as well. The only qualm I have is that the magazine seems oddly scaled. Id like to see the mag end about a close to the trigger group as it does, but extend to much closer to the end of the magwell, similar to an AR-10.
For the fron attachment, I was thinking about something like these magazines OpsGear used to make: